Quiet snap action electric switch



8- 25, 1970 R. G. MUNROE 3,525,834

QUIET SNAP ACTION ELECTRIC SWITCH Filed June 6, 1968 2 Sheets-Sheet 1 PINVENTOR.

RONALD G. MUNROE I 00 65 8522 33 a0 20 I ATTORNEYS Aug. 25, 1970 R. G.MUNROE QUIET SNAP ACTION ELECTI QIC SWITCH 2 Sheets-Sheet 22 Filed June6, 1968 FIGJO M mm T U M M V G L .A w p R t Q g m Y B ATTORNEYS UnitedStates Patent 3,525,834 QUIET SNAP ACTION ELECTRIC SWITCH Ronald G.Munroe, Old Bridge, N.J., assignor to Eagle Electric Mfg. Co.,Incorporated, Long Island City,

N.Y., a corporation of New York Filed June 6, 1968, Ser. No. 735,148Int. Cl. H01h 21/40 U.S. U. ZOfi bB 12 Claims ABSTRACT OF THE DISCLOSURESingle contact and double contact switches are disclosed using a ball atthe top of a spring for obtaining the snapaction. In the single contactswitch, a toggle lever, in one position, spaces the ball from themovable contact, and in another position causes the ball to press themovable contact arm against the stationary contact. These parts aremounted in an open top insulating casing which also contains the contactterminals therewithin. An insulating cover plate received within theopen end of the casing, has a pair of downwardly facing half bearinggrooves which are located above the top ends of pillars in the casing.The cover plate has a large slot to pass the handle of the toggle leverwhich has a pair of oppositely extending central, transverse trunnionsreceived in said bearing grooves. A downwardly extending wedge in thetoggle lever engages the spring mounted ball. A rubber pad is insertedunder the cover plate and overlies a pair of abutment posts in thecasing disposed in a plate perpen dicular to said pillars and disposedtherebetween. The ends of the rubber pad are adapted to be engagedalternately by outwardly extending arms on the toggle lever as thetoggle lever is oscillated. Contact of these arms with the rubber pad issilenced because of the resiliency of the rubber pad. The rubber pad hasa central hole through which the wedge on the toggle lever projectsdownwardly. The rubber pad is squeezed between the upper ends of thepillars and the trunnions to frictionally bind the toggle lever andprevent slop and eliminate noise of operation of the lever.

A tongue on the rubber pad projects down from one end of the opening inthe pad, to lie between the side of the ball remote from the movablecontact arm and the adjacent post to provide a noise reducing abutmentfor the ball to hit against when it moves away from the movable contact.This tongue is narrow enough to move between the two pillars and intothe ball passage, and stops the ball so thtt it has less travel until ithits the movable contact in the on" position. This reduction of travelreduces some of the momentum from the ball when fiipped to the onposition and further silences the switch.

The double contact switch has two movable contacts disposed on oppositesides of the ball and incorporates a similar rubber band to squeezebetween the trunnions and the upper ends of the pillars, and to becontacted by the arms of the toggle lever.

BACKGROUND OF THE INVENTION Field of the invention This inventionrelates to a snap-action toggle lever operated switch with means tosilence the switch and to eliminate slop in the action of the togglelever.

Description of the prior art Snap-action switches with contact dampeningmeans have been known. In one such device, rubber sleeves are placedaround the posts and the ball is pressed by the toggle lever to move amovable contact against a sleeve in on position and the ball against theopposed post in oil position. No means was provided in such device toremove slop from the toggle lever or to prevent noise of operation ofsaid lever.

In another prior device, the fixed contacts were mounted on rubberbumpers but did not eliminate slopin the action of the toggle lever.

In yet another prior device dampening means was interposed between thelayer and the movable contacts but no dampening means was interposedbetween trunnions and their hearing, or between the ball and a fixedpost of the housing.

In yet another prior art device, a toggle lever has a cam to contact andrub against a resilient cover plate for the switch housing to retardmotion of the toggle lever.

Other objects of this invention will in part be obvious and in parthereinafter pointed out.

The invention accordingly consists in the features of construction,combinations of elements, and arrangements of parts which will beexemplified in the constructions hereinafter described, and of which thescope of invention will be indicated in the following claims.

BRIEF DESCRIPTION OF THE DRAWING In the accompanying drawing, in whichare shown various illustrative embodiments of this invention,

FIG. 1 is a top plan view of a single contact switch embodying theinvention;

FIG. 2 is a cross-sectional view taken on line 2-2 of of FIG. 1 andshowing the switch in ofi position;

FIG. 3 is a partial view similar to FIG. 2, but showing the switch in onposition;

FIG. 4 is a cross-sectional view taken on line 44 of FIG. 2;

FIG. 5 is a partial top view similar to FIG. 4, but showing the onposition of the switch;

FIG. 6 is a perspective view of the rubber pad shown in FIGS. 2, 3, 4and 5;

FIG. 7 is a top view of a double contact switch embodying the invention,but with the strap and housing cover removed;

FIG. 8 is a cross-sectional view taken on line 8-8 of FIG. 7;

FIG. 9 is a cross-sectional view taken on line 99 of FIG. 7; and

FIG. 10 is a perspective view of the rubber pad shown in FIGS. 8 and 9and shown in dot-dash lines in FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now in detail to thedrawing, FIGS. 1 to 6 illustrate a single contact switch 10 embodyingthe invention.

Switch 10 comprises a metal strap 11 clamping a cover plate 13 to a case12. Said cover serves to hold a toggle lever 14 in operative positionrelative to the case for actuating a movable contact 15. The case 12 andcover 13 comprise a casing. The cover has end internal positioningshoulders extending into the case 12.

Said case 12, cover 13 and toggle lever 14 are made of moldedelectrically insulating rigid material, and strap 11 is made of sheetmetal, as a stamping.

Case 12 comprises a bottom wall 18 from the ends of which, end walls 19and front and rear walls 20 project upwardly. Walls 20 interconnect endwalls 19. Said walls 19, 20 have coplanar upper end edges 19a, 20a.

Case 12a of a double contact switch 10a illustrated in FIGS. 7 to 10, issubstantially similar to casing 12, with exception of some details whichwill be referred to hereinafter, and the same reference numerals will beused for similar parts of cases 12 and 1211. Some details of the case 3are more clearly illustrated in FIGS. 7 to 10 than in FIGS. 1-6. Theleft end of the drawing of case 12 is shown at the right end of thedrawing of case 12a.

Thus case '12a also has a bottom wall 18, end walls 19 having upperedges 19a and front and rear walls 20 having upper edges 20a. Each ofend walls 19 has a central vertical outer recess 23 which narrows at itsupper end as at 24, between a pair of spaced, aligned horizontalledges25 projecting outwardly from the upper end of said end wall. Theundersides of the inner ends of said ledges 25 form undershoulders 26for the purpose hereinafter appearing.

Cases '12, 12a are each formed adjacent the underside of the bottom wall18 and adjacent one end, with downwardly projecting projections 27formed in case 12a with through openings 28 and with through slots 29adjacent said projections. Said openings and slots are eliminated at oneend of case 12.

Both cases 12 and 12a are formed with a pair of integral parallelupstanding pillars 30 having narrowed rib tips 31. The upper end edges32 of tips 31 are aligned and are disposed in a plane substantiallyslightly above the level of the underside of cover 13.

Said pillars 30 are spaced equally from end walls 19; are spacedinwardly from front and rear walls 20; and extend upwardly from thebottom wall :18. Said pillars have shoulders 33 disposed in a planeslightly below upper edges 32.

.Both cases, 12, 12a are formed with integral abutment posts 35 whichextend upwardly from the bottom wall 18 and are disposed in alongitudinal central plane perpendicular to the bottom wall. Said postsare hence in a plane spaced centrally between pillars 30. Posts 35 areconnected near bottom wall '18 to end walls 19 by webs 36. Between posts35 and also between pillars 30 is a central vertical socket 37 having anupwardly extending central pin 37a for the purpose hereinafterappearing.

Walls 20 are formed with aligned through openings 40 extending up frombottom wall 18. Said openings 40 have upper semi-circular edges 41.Bottom wall 18 is notched as at 18a at the lower ends of openings 40.

The cover 13 fits into the upper end of case 12 (or 12a) and has anundersurface disposed in a plane above the plane of the upper ends ofposts 35; and somewhat above shoulders 33 of pillars 30. Said coverrests on internal corner shoulders 13a and has a central longitudinalthrough opening 44, an upper perimetral shoulder 45 and a rectangularportion 46 projecting up above said shoulder 45. Shoulder 45 surroundssaid rectangular portion 46. The ends of slot 44 may be upwardly andinwardly curved. The cover has end walls 47 interconnected by front andrear portions 48. Portions 48 have at their inner surfaces, centralnotches (half bearings) 50, semi-circular in shape at their upper ends,thereby forming half hearings on which to rock or oscillate the togglelever I14, as will appear hereinafter.

The cover 13 is held clamped to the casing 12 by said strap 11 in themanner to be explained. Said strap 11 has a flat central portion formedwith a central rectangular opening 56 the edges of which rest onshoulder 45; and said portion 46 of the cover projects upwardly throughsaid opening. Said strap has downwardly bent inverted T- shaped portions58, cut from the metal of the strap, each comprising a narrow portion 59passing through narrow, slot portion 24, and a wide crossing portionengaging in slot 23 and beneath the ledges 25 to hold the strap to thecase 12. Strap 11 may be of conventional construction.

The toggle lever 14 comprises a central upwardly extending handle 60from the lower end of which extend arms 61 disposed longitudinally ofthe slot 44, Extending sideways from the lever are similar, oppositelyextending, aligned trunnions 62 projecting into the half bearing notches50, whereby to permit said toggle lever to be rocked or oscillated. Arms61 may be hollowed as shown at 63 to reduce weight. As the lever 14 isrock-ed, one arm moves down toward the upper end of one abutment 4 post35, while the other arm moves away from the other post.

Projecting down at the underside of said lever is a central lug or wedge65 located between pillars 30 and also between posts 35.

Disposed in socket 37 is a coil compression spring 70 at the upper endof which is mounted a steel ball 71 which engages the lower end or tipof the wedge 65. The centering pin 37a projects up into the lower end ofspring 70. The ball releasably retains the toggle lever in one or theother of its extreme angular positions by reason of being pressed byspring 70 against one side or the other of the tip of wedge 65. Theupper end of ball 71 is substantially at the level of the upper ends ofposts 35 and the tip of wedge 65 projects somewhat therebelow.

Mounted in one end of cases 12 and 12a, on bottom wall 1 8 and onopposite sides of the adjacent post 35 and web 36, are spring contacts80. The contacts are located at the left end of case 12 and at both endsof case 12a.

Each contact has a vertical arm 80a contacting a pillar 30, a horizontalportion 80b extending therefrom and resting on bottom wall 18 and aspring finger 80c inclined upwardly and outwardly from portion 80b andoverlying an opening 28.

Also at the left end of case 12 (and both ends of case 12a) there is acontact comprising a wall 85a contacting the inner side of a wall 20(lower wall 20 as shown in FIG. 4 and upper wall 20 as shown in FIG. 7).Wall 85a covers opening 40 of the adjacent wall 20 of the case. Wall 85ahas an extruded internally threaded boss 85b which receives the shank86a of a screw 86. The head 86b of said screw can fit in said opening 41and constitutes a terminal post for a conductor wire. Extending at rightangles to wall 85a is a wall 850 contacting an adjacent end wall 19 andhaving edge contact with web 36. Wall 85c is formed with an innervertical groove 85d disposed above one opening 28. A conductor wirepushed up through hole 28 is gripped between inclined tongue 80c andWall 85c.

Wall 85a is formed with a horizontal pocket disposed in a vertical planeto fixedly receive one end of a movable contact member 87 which has aspring ann 87a traversing the casing and disposed between the adjacentpost 35 and the ball 71. This arm carries the movable contact 15. Thearm 87a is disposed between pillars 30 and said adjacent post 35 (shownat left side of FIG. 4).

Referring now specifically to case -12 and FIGS. 1 to 6, it will be seenthat a second contact 90 is disposed at left end of said case and issubstantially similar to contact 85 and is substantially symmetricalthereto. However, contact 90 is formed at the inner side of wall 90a(corresponding to wall 85a of contact 85), with an offset arm 90bconstituting a fixed contact disposed in opposed aligned relation to theouter end of movable contact arm 87a.

In the position of FIG. 2, the switch is off, and the tip of wedge 65 islocated between the movable contact arm 87a and the ball 71. When thetoggle lever is rocked from the position of FIG. 2 to the position ofFIG. 3, the ball is first depressed against spring 70, and then as thewedge rides over the ball, said ball springs up on the opposite side ofthe wedge 65 and presses the movable contact against the fixed contactfor achieving the on position. In both positions, the spring pressingthe ball against wedge 65, releasably holds the toggle lever in oneposition or the other.

Highly improved means is provided to silence the switch 10. To this enda fiat pad or piece of rubber or neoprene or other elastic rubber-likeor soft padding damping material is placed over the upper ends of posts35. Pad 100 may be rectangular shape and has a tongue 101 cut from thematerial thereof and depressed to form an opening 103. The ends of thepad rest on the upper surface of abutment posts 35. The central portions102 of the pad, on opposite sides of opening 103, overlie the upper endsof pillars 30 and are squeezed between the trunnions 62 and the upperedges of pillar portions 31 forcing the trunnions to bottom in the halfbearings 50. Thus parts of portions 102 of the pad project up intogrooves 50 in the cover 13. Most of the noise in a switch of this typeis occasioned by the slop of the toggle lever pivots or trunnions whenthe switch is thrown. The friction of the rubber pad between thetrunnions and the pillars and the consequent friction between thetrunnions and the half bearings eliminates this slop.

The tongue 101 is disposed between the ball 71 and the post 35, remotefrom the movable contact in the oil position of the switch. The tongueis narrow enough to move between pillars 30 into the ball passage. Thewedge 65 projects down through hole 103.

As shown in FIG. 2, the tongue 101 may move between pillars 30. Thuswhen the toggle lever moves from position of FIG. 2 to the position ofFIG. 3, the ball having been moved to the left by tongue 101, as shownin FIG. 2, has less length of travel before it strikes the movablecontact to move it into engagement with the fixed contact as shown inFIG. 3. This reduction of travel takes some of the momentum away fromthe ball when flipped to the on position and silences the switch.

When the toggle lever is thrown, one or the other end of arms 61 of thetoggle lever contacts the pad 100 which provides a dampening of noisefor the ends of the lever. Ordinarily, if the ends of the lever were tostrike solid mold material (such as Bakelite), in contacting the upperends of the posts 35, they would create clicking noises.

The ball, when moving from on to off position, is prevented fromstriking the inside of the post 35 at the right side of FIG. 3, byreason of the intervening flap or tongue llllll which dampens the noiseand prevents clicking.

Referring now specifially to case 12a and the double throw contactswitch a of FIGS. 7 to 10, it will be seen that this switch has twocontacts 85 along the wall (shown at top of FIG. 7). These contacts 85are symmetrical with respect to each other and carry screws 86 andcooperate with contacts 80 at both ends of the casing.

At the left end of said wall 20 there is also an opening 40 to receivethe head of screw 86. In FIG. 7, the screws 86 (at the top of saidfigure) are shown partially unscrewed, only for purpose of illustration.

At the wall 20 shown at bottom of FIG. 7 there is a single contactmember 110 which comprises two fixed contacts 112 joined together by acentral portion 111.

As the toggle lever 14 of switch 10a is flipped, in either direction, aclosed contact is opened and an open contact is closed.

Interposed between the toggle lever and the upper ends of posts 35 andpillars 30 is a pad or plate 120 of rubber or rubber-like material suchas neoprene or any other soft padding or damping material.

Pad 120 has a central rectangular hole 121 through which the wedge 65projects downwardly and is engaged by the ball 71. The ends of pad 120are alternately contacted by the undersides of the arms 61 of the togglelever to dampen or eliminate noise. Portions .122 of the pad on oppositesides of hole 121 are squeezed between trunnions 62 and upper ends ofpillars 30 to create friction as aforementioned and prevent slop betweenthe toggle lever and the casing.

It will be observed that case 12 must be made with openings 40 at oneend only (left ends of walls 20 in FIG. 4). Case 12a has two openings 40on one wall 20 (top wall shown in FIG. 7), and only one such opening 40on the other wall 20 (shown at lower side of FIG. 7).

Therefore, only one end of contact 110 (right end as shown in FIG. 7)carries a screw 86.

It will thus be seen that there are provided articles in which theseveral objects of this invention are achieved,

and which are well adapted to meet the conditions of practical use.

As possible embodiments might be made of the above invention, and asvarious changes might be made in the embodiments above set forth, it isto be understood that all matter herein set forth or shown in theaccompanying drawings, is to be interpreted as illustrative only.

I claim:

1. A switch comprising a casing a toggle lever, means for mounting saidlever in said casing for oscillatory movement, said mounting meanscomprising trunnion means on said lever, bearing means in said casingreceiving said trunnion means, pillar means in said casing, said pillarmeans being directly opposed to said bearing means and means interposedbetween and contacting said trunnion means and said pillar means to holdsaid trunnion means against said bearing means and to prevent a sloppyfit between said lever and said casing, said lever having a portionprojecting through an opening in said casing for manual engagement tooscillate said lever, means for resiliently urging said lever toward andfor releasably retaining said lever at alternate opposite ends of itsangle of oscillation, normally open contacts in said casing, said urgingand retaining means including means to close said contacts in one endposition of said toggle lever and to allow said contacts to open in theopposite end position of said toggle lever, said lever having a pair ofoppositely extending arms, rigid abutment means in said casing, andshock absorbing means interposed between said abutment means and armsand positioned to be alternately struck by said arms, respectively, assaid lever is oscillated, to dampen noise, said shock absorbing meansand said hold and prevent means comprising difierent parts of a singlepad of rubber-like material.

2. A switch comprising a casing, a toggle lever, means for mounting saidlever in said casing for oscillatory movement, said lever having aportion projecting through an opening in said casing for manualengagement to oscillate said lever, means for resiliently urging saidlever toward and for releasably retaining said lever at alternateopposite ends of its angle of oscillation, normally open contacts insaid casing, said means for resiliently urging said lever comprising acoil compression spring in said casing and a ball mounted on one end ofsaid spring, said lever having a lug to engage, depress and ride oversaid ball as said lever is oscillated, said ball closing said contactsin one end position of said toggle lever and allowing said contacts toopen in the opposite end position of said toggle lever, said leverhaving a pair of oppositely extending arms, rigid abutment means in saidcasing, and shock absorbing means interposed between said abutment meansand arms and positioned to be alternately struck by said arms,respectively, as said lever is oscillated, to dampen noise, said shockabsorbing means comprising a pad of rubberlike material on said abutmentmeans having an integral tongue out from said pad and projecting betweensaid abutment means and ball, on one angular position of said lever.

13. The combination of claim 1, said trunnion mounting means comprisinga pair of oppositely extending aligned trnnnions on said lever, saidbearing means comprising a pair of bearings receiving said trunnions,said pillar means being directly opposed to said bearing means, saidpillar means comprising a pair of spaced pillars integral with saidcasing, said means interposed between said abutment means and armscomprising a pad of rubber-like material, and said shock absorbing meansinterposed between said pillar means and said trunnion means comprisingspaced portions of said pad interposed between said pair of pillars andsaid pair of trunnions.

4. The combination of claim 3, said means for resiliently urging saidlever comprising a coil compression spring in said casing, a ballmounted on said spring, said 7 lever having a lug to engage, depress andride over said ball as said lever is oscillated, said pad having anintegral tongue cut from said pad and projecting between said abutmentmeans and ball in one angular position of said lever.

5. The combination of claim 2, said tongue when depressed from the planeof said pad forming an opening, and said lug projecting through saidopening in said pad.

6. The combination of claim 1, said means for resiliently urgng saidlever comprising a coil compression spring in said casing, a ballmounted on one end of said spring, said lever having a lug to engage anddepress said ball and ride over said ball, as said lever is oscillated,said pad comprising an integral tongue out from said pad, said abutmentmeans comprising a pair of posts integral with said casing, said tongueprojecting between one of said posts and said ball, in one angularposition of said lever, and between said lug and said one of said postsin the opposite position of said lever.

7. The combination of claim 6, said tongue when moved out of the planeof said pad, forming an opening in said pad, and said lug projectingthrough said opening in said pad.

8. The combination of claim 4, said tongue being narrower than the spacebetween said pillars and movable between said pair of spaced pillars topush said ball toward said contact when said contacts are in opencondition.

9. The combination of claim 7, said pillar means comprising a pair ofspaced pillars, and said tongue being movable between said pillars.

10. A switch comprising a casing, a toggle lever, means for mountingsaid lever in said casing for oscillatory movement, said lever having aportion projecting through an opening in said casing for manualengagement to oscillate said lever, means for resiliently urging saidlever toward and for releasably retaining said lever at alternateopposite ends of its angle of oscillation, normally open contacts insaid casing, said urging and retaining means including means to closesaid contacts in one end position of said toggle lever and to allow saidcontacts to open in the opposite end position of said toggle lever, saidlever having a pair of oppositely extending arms, abutment means in saidcasing, said means for resiliently urging said lever comprising a coilcompression spring in said casing, a ball mounted on one end of saidspring, said lever having a lug to engage, depress and ride over saidball, as said lever is oscillated, and a pad of rubber-like materialwithin said casing having an integral tongue projecting between saidabutment means and ball in one angular position of said lever.

11. The combination of claim 10, said means for resiliently urging saidlever comprising a coil compression spring in said casing, a ballmounted on one end of said spring, said lever having a lug to engage,depress and ride over said ball, as said lever is oscillated, abutmentmeans within said casing, and shock absorbing means disposed betweensaid abutment means and ball in one angular position of said lever.

12. The combination of claim 11, said tongue and said interposed meanscomprising parts of a single rubberlike pad.

References Cited UNITED STATES PATENTS 1,415,972 5/1922 Allen 200681,877,923 9/1932 Lucia 20068 2,648,73 1 8/ 1953 Despard. 3,172,972 3/1965 Schleicher. 3,182,161 3/1965 Winter.

ROBERT K. SCHAEFER, Primary Examiner D. SMITH, JR., Assistant ExaminerUS. Cl. X.R. 20067, 166

